Process of producing alkyl sulphates



Jan. 21, 1930. Rf M. lsHAM ET AL I PROCESS OF PRODUCING ALKYL SULPHATES Original Filed May l, 1919 Patented Jan, 21, 1930 'UNITED STATES `a'rsrrr oFFic's ROBERT M. ISHAM, OF OKMULGEE, AND SIDNEY BORN, OF TULSA., OKLAHOMA, .AS- i SG-NORS, BY MESNE ASSIGNMENTS, T SE'I'H B. HUNT, TRUSTEE, OF MOUNT KISCO,

New Yoan a PROCESS OF PRODUCING ALKYL SULPHATES Original application filed May 1, 1919, Serial No. 294,013. Divided and this application filed August 7,

1926, Serial No. 127,948.'

l'lhis invention relates to a process or' producing alcohols and mixtures of alcohols from hydrocarbons.

Various processes have been proposed 'for the recovery of alcohols from gases Aformed in the decomposition of hydrocarbon materials. When the object is to produce ethyl alcohol the gases are first thoroughly puriiied to remove the higher olefincs and the puried gas is treated to produce the alcohol. When the object is to produce the higher alcohols the gases are dissolved directly in sulphuric acid and the resulting material treated to recover thealcohols. These processes have the disadvantage that the higher olefines contained in the gas are polymerized by this treatment with the result that the yield of alcohol is materially reduced and that the polymerization products cause difficulties in the later steps of the process.

The present application is a division of our copending application Jfor process of producing alcohols, Ser. No. 294,013 tiled May 1, 1919.

It is an object o-'r'` the present invention to provide a process in which a high yield of alcohol is obtained from oil gases without polymerization of the higherroleiines.

lt is a ,further object of the invention to y provide a process in which the olefines are selectively absorbed to yield different alcohols from the complex mixtures of oleiines obtained from oils.

With these and other objects in View lthe invention consists in the'process of making alcohols hereinafter described and claimed.

In the accompanying drawings is shown a diagrammatic illustration of an apparatusv Renewed May 27', 1929.

tain large amounts of ethylene and also considerable amounts of higher olefines, such as amylenes and butylenes. The gases evolved on cracking petroleums under higher pressures contain large amounts of butylenes and amylenes with small admixtures `of other oleiines. s

To obtain alcohols from oil gases in accordance with the preferredform of the invention7 the gases from a cracking retort are first compressed and cooled. A small amount ot' water and some hydrocarbon vapors will be condensed at this point in the process and these are removed to be blended with gasoline. rl`he cooled and compressed gases containing the oleines are then led into the first of a series of absorbing units. come in contact with sulphuric acid cooled to a temperature of about 25 C., which acid contains sulphuric acid esters of lower alcohols formed by the absorption of olefines at a later stage in the process.. In this unit the higher oleiines, such as `amylene's and butylenes, are absorbed to forni esters of the corresponding alcohols. From the first absorbing unit the gases pass toa seeond'absorbing unit in which the lower olefines, such as propylene, are absorbed to form the corresponding esters. The sulphuric acid in the second ,unit is at a higher temperature and contains esters of still lower alcohols obtained in 'a Here they Y later absorption unit. From the second absor'bing unit the gases, which now contain only the lowest members ofthe oleiines, pass to the finalabsorbing unit where they come in contact with concentrated sulphuric acid maintained at a higher temperature than the temperature of the second unit. Here the ethylene is absorbed to form ethyl sulphuric acid. The sulphurie acid is passed from the iinalto the first absorption unit counter'to the current of gas. The esters obtained in the above manner may then be hydrolyzed and distilled to obtain the corresponding alcohols.-

In the drawings is illustrated a diagrammatic apparatus or flow sheet in which the vpreferred process of the invention may be carried'out as follows: 1

` Oil gases from a gasometer, or other source 10, flow to a compressor 12, Where they are compressed to a pressure of from 50 to 200 pounds per square inch. The compressed gases then pass through a condenser 14 Where they are cooled to such a temperature that part of the Water and some hydrocarbon vapors are condensed. These gases then pass into a separator 16, Where entrained liquid particles are separated therefrom. The liquid from the separator 16 is then passed to a gasoline blending apparatus 18 and agitator 20, and from thence to storage.

The gases leaving the separator 16 pass to the first absorber 22 of an absorbing unit 22, 24, 26 and 28. These absorbers 22-28 may be of any standard type capable of being cooled tothe desired temperature and of bringing the oleines in the gases into intimate Contact With an absorbing acid solution. The gas enters the first absorber 22 of the unit by a pipe 30 and passes from this absorber to the second absorber 24 by a pipe 32. It then passes in a similar manner to the absorbers 26 and 28 by means of pipes 34 and 36. By-pass pipes 38, 40, 42 and 44 are provided whereby any of the absorbers 22-28 may be cut out ot' the unit. In the piping arrangement, suitable valves (indicated as crosses on the pipes) are provided to obtain the desired circulation of gas and liquids. The acid which is used to absorb the oletines passes from a cooler 46in a reverse direction to the direction of the iow of the gases through absorbers 28, 26, 24 and 22 by means of the respective pipes 48, 50, 52 and 54, and leaves the unit thru a pipe 56. (Each of the absorbers 22-28 is maintained at a temperature of about 25 C. at which temperature the amylenes and butylenes are selectively absorbed from the mixture of gasses to form theeorresponding esters.

When a mixture of oletines, such as exists in oil gases, is brought directly into contact With sulphuric acid at the usual atmospheric temperatures, the greater part of the higher olefnes, the butylenes, -amylenes and hexylenes, are polymerized and do not form the esters of the acid. This polymerization causes a decreased yield of higher alcohols, particularly of secondary and tertiary amyl and butyl alcohols, and also produces substances Whi'ch interfere With the separation of diolefins inlthe dilution tank. We have discovered that when a very low temperature, that is a temperature of about 25 C..

is employed CWhile carrying outrnthe absorption under pressure, this polymerization is `very much reduced. At these-"lower temperatures, mo1eover,the lighter olefines, the p ropylenesl and ethylenes, are not appreciably absorbed. By usingthese low temperatures, therefore, the higher olefines may be selectively-.absorbed and a much higher yield of the higher alcohols may be obtained. ,With some oil gasesthe higher olefines may be effectively esterified at temperatures as high as h5 C., but with gas containing a higher percentage of higher olefines the lower temperatures are preferred. I

7e have, moreover, found that the polymerization of the higher oletines may be rcduced to a negligible amount if the sulphuric acid used contains lower olelines which are present in the form of the sulphuric esters of lower oleiines. Therefore, we use as an absorbing medium, sulphuric acid'which has been used as an absorbent for the lower olefines in later steps of the process, and which has become diluted thereby. However', with certain types of gases, sulphuric acid which does not contain lower olctnes may be used Without forming a prohibitive amount of polymerization products. In this case fresh sulphuric acid may be supplied at the proper temperatures to each stage of the absorbing operation. f

From the first absorbing unit the gases, noW freed from the higher oleines, pass thru a pipe 63 to absorber64 of a secondy absorbing unit 64, 66, 68 and 70, which has a construction and piping arrangement similar to the construction and piping arrangement higher temperatures, particularly When the amylenes and butylenes have been 'previouslyremoved. Ethylene, Which-is not readily absorbed at this temperature, passes out of the unit With the gases leaving absorber 70.

From the second absorbing unit the gases, which non7 contain practically no olefines except ethylene, pass through the third absorbing unit consisting of absorbers 76, 78, 80, and 82. These absorbers have a construction and piping arrangement similar to the construction and piping arrangement of the absorbers of the first and second units. Concentrated sulphuric ac id is introduced into the third absorbing uriiit thru a pipe 84 and flows thru the .unit `()'unter-current to the yflow of gas. A temperature of'approximately of the first absorbing unit. The gases pass 90 C. is maintained in the third absorbing unit, at which temperature the/ethylene is I readilyj'absorbed with the formation of ethyl n sulphuric acid. The unabsorbed gases then pass from the apparatus thru pipe 83, and may be conducted to storage or to a` furnace tobeburned.

' system, is as follows:

maare/i VthroughV the units 82, 80, 78 and; 76 and through a .pipe 90 and valve 91 to the pump 92. Pump 92 forces the acid liquor through the cooler 72 to the last absorber 70 of second absorbing unit, and it then ovvs'through the absorbers 70,68, `66 and 64 and through pipe 74 and valve 75 to a-pump 94. The pump 94 forces the acid through the cooler 46 and through the first absorption unit. Coolers 46 and 72 may form a part of the corresponding absorption units 22-28 and 64-70, or in case suiicient cooling eii'ect can be obtained in the absorbers themselves these preliminary coolers 46 and 72 may be omitted entirely. The

l acid liquor flows from the absorber 22 of the first absorption unit tothe separator 58 Where the unabsorbed condensate is removed. The acid liquor, which has become diluted by the 'absorbed oleiines and moisture not removed from the gases and which now has a specific gravity of about 0.95,passes to a dilution ytank 96 and the unabsorbed condensatepasses l agitator 20.

lln the dilution tank 96, the acid liquor is to the gasoline'blending apparatus 62 and diluted with approximately three volumes of lvvater for each volume of acidoriginally supplied to the absorber whereupon any olefines I acid solution is' then hydrolyzed 1n the tank Whichmay have'been polymerized during the process separate out and are removed to a diolefine tank'98. From the dilution tank the dilute acid liquors flow to a still 100, Where the mixtures of the esters are hydrolyzed and disi tilled. The heavier alcohol vapors from the still 100 are collected in acondenser box 106 and drawn oto a storage tank 108. The al.

` cohol is then taken to a rectifying still 110,

Where the vapors are selectively separated and condensed in the condenser 112, and run I into storage tanks 114, 116 and 118 (forfamyl,

butyl and propyl alcohols respectively). The ethyl alcohol is condensed in a condenser 120 and stored in a tank 122 or rectied in a still 124. The vapors from the still 124 are -condensed in a condenser 126 andlthe finished product stored in a tank 128. The dilute acid remaining after distillationin the still 100' is drawn off to a dilute acid storage tank 130. This acid may be brought to the lead pans 132 and'still 134 to be concentrated and then returned to the tank 86 to re-enter the process.

If desired, the condensates from the condenser boxes 112 and 126 may be passed through calcium chloride driers to be dehydrated be- `fore'they are sent to the storage tanks 114,

' 116, 118 and 128.

When it is desired to produce separate soluferent absorbing units, acid from the storage tank 86 is separately circulated through each of the absorption units. The acid to be used for absorbing the higher oleiines, such as amylene and butylene in the first absorbing unit i's then taken directly from the storage tank 86; or other source, by the pump 94 through a pipe`136 and forced directly in the second absorption unit 64-70, for sepv arately recovering the propylene,.is taken by the purnp92 dir-ectly from the storage tank .86 through a pipe 138 and forced through the cooler 72 to the second absorption unit. The acid containing propyl esters is then removed from the `absorber 64 of' the unit 64-70 through a valve 140 and pipe 142. The acid solution is then hydrolyzed in the tank 144 and then separately treated in stills 100 and 110to recover propyl alcohol. The acid to be used in the ithird absorption unit 76-82, forl separately recovering the' ethylene 'is taken by the pump 88 directly from the storage tank 86 through a pipe 84 and forced to the third absorption unit. The acid containing the ethyl esters is then removed from absorber' 7 6 of the unit 76-82 through a valve 146 and pipe 1,48 tol a dilution tank 150. The

150 and is then separately treated in stills 100 and 110 vto recover the ethyl alcohol.

sure to assist in an effectiveselective absorption and to provide a minimum polymerization ofthe olefines. The oil gas is placed under pressure by the compressor 12 and the acid is placed under pressure by the pumps 88, 92 and 94 In accordance With the gas being treated and the type of esters being formed, a pressure of from 50 to 200 pounds per squareinch is maintained in the absorbing units. a

The use of separate portions of sulphuric acid in each of the absorbing units has the advantage of forming separate solution of the esters, and may be used with some types of gases Without substantial losses by polymerization.' l

With the above process the most complex mixtures 'of gases can be treated so as to sclectively absorb the various oleines under those conditions which are most suitable for the absorption of each individual olefine. Moreover, the process canbe so vmanipulated as to produce amixture of esters with a minimum of polymerization fproducts.

The above detailed description of the procllO ess is merely given by way of example as one embodiment which has given excellent results in practice. It is evident that modifications may be introduced in some of the steps of the process, that the types and numbers ofabsorbers may be varied to suit different types of gases an'd that the treatment of the products obtained in different steps may be varied without departing from the fundamental features of the invention.

In making mixtures of alkyl sulphates the proper temperature conditions may in some cases be maintained in using less than three absorbing units and it may then be of advantage to use two units. While the process has been described as carried out in stages in separate absorbing units as this method appears to permit of better temperature control, this may be varied by not dividing the absorbers in separate units and by passing the gas and acid counter current to each other and gradually and continuously increasing the temperature in the direction in which the gas Hows.

We claim:

1. The process of making alkyl sulphates from gases containing butylene, propylene and ethylene which comprises treating the gases in three successive stages or steps with sulphuric acid, the rst two stages being conducted at temperatures adapted for the absorption of butylene and propylene respectively and the last stage at a temperature adapted for lthe absorption of ethylene, to separately absorb the several oleines substantially in the order of chemical aiiinity, whereby alkyl sulphates corresponding to the several oleines are separately produced.

2. The porcess of making alkyl sulphates from4 gases containing butylene, propylene and ethylene whichv comprises passing the gases successively through a series of absorbing chambers containing sulphuric acid under varying temperature conditions such that the olefines are absorbed substantially in order of chemical aiiinity and under conditions most suitable for the fixation of the respective oleiines, the temperature of the propylene absorbing chambers being under about 209 C. and that of the ethylene absorbing chambers being ap'poximately 90 C. whereby alkyl sulphates corresponding to the several oleines are separately produced.

3. The process of making alkylssulphates from olonne-containing gases, comprising treating the gases in successive stages with sulphuric acid at successively increased temperatures, the temperature at each stage being such as to promote the selective -absorp tion of the olvenes from said gases, and sepa rately removing the olefines absorbed in each stage.

4. The proce'ss of making alkyl Sulphates from material containing butylene, propylene and ethylene, comprising contacting said of their chemical affinity and separately col-l lecting the alkyl sulphates formed in the respective groups of chambers corresponding to the several oletines selectively absorbed I from the gases.

6. The processof making alkyl sulphates from gases containing butylene and propylene which comprises passing the gases through a plurality of series-connected chambers, contacting gases in certain of said chambers withl sulphuric acid of a temperature adapted for the absorption of the butylene and subse uently contacting the gases in other cham ers with sulphuric acid of a temr perature adapted for the absorption of the propylene `whereby corresponding alkyl sulphates are separately produced.

7. The process of making alkyl sulphates from oleline-containing gases comprising contacting said gases with sulphuricacid in av plurality of interconnecting chambersfdivided into a plurality of operating groups, introducing fresh sulphuric acid into a chamber of each group, maintaining in each group a temperature adapted to promote the selective absorption of an individual olefin from said gases, and separately withdrawing the absorbed products from each group.

8. In theprocess of making alcohols fromv olen containing'hydrocarbons, passing sulphuric acid in parallel through a plurality of groups of absorbing chambers, passing f the hydrocarbons to be treated in series through the chambers of each group, maintaining each group of chambers at a tempera-A ture adapted to promote the selective absorption of a desired olefin from said hydrocarbons, and separately removing the absorbed products from each group of absorbing chamers.

9. In the vprocess of making alcohols from oil gases containing olefins, passing sulphuric acid in parallel through a pluralityof absorbing zones, passing the oil gases to be treated in series through said zones, and maintaining said zones at successively higher temperatures, the last zone `of said 'series being maintained at approximately 90o C.

10. The process as delined in claim 9' in which the rst absorbing zone is maintained at a temperature of about 25 C.

11. The process as defined in claim 9 in' Which an intermediate zone is maintained by regulated cooling at a temperature of from 10 to 20O C.

12. The process of making acid aykyl sulphates from gases containing butylenes and propylene Which comprises passing the gases' through`a plurality of series-connected chambers, contacting the' gases in certain of said chambers With sulphuric acid of a concentration and temperature adapted for the absorption of the butylenes, and subsequently contacting the gases in other chambers With sulphuric acid of a concentration and temperature adapted for the absorption ot the propylene whereby corresponding acid alkyl sulphates are separately produced.

13. The process of making alkyl sulphates from hydrocarbon material containing oletins, which comprises passing sulphuric acid in parallel througha plurality of absorbing Zones, passing the hydrocarbon material to be treated in series through said zones, maintaining each Zone at a temperature adapted to promote the selective absorption of a desired olefin from said hydrocarbon material, maintaining a superatmospheric pressure on the materials undergoing absorption in said Zones, and separately removing the absorbed products from each zone.

14. The process of making alkyl sulphates from hydrocarbon material containing olefins, Which comprises introducing fresh sulphuric acid into each of a series of zones maintaintl :it successively higher temperatures, introducing the hydrocarbon material to be treated into the lowest temperature zone of the serie.Q and passing the unabsorbed material from said zone successively into the remaining zones of the series, bringing the hydrocarbon material introduced into each Zone into intimate contact with the sulphuric acid therein, maintaining a superatmospheric pressure on the materials in each zone, and 1naintaining a temperature adapted to promote the selective absorption of desired olefin constituents from said material, and separately removing the absorbed olefin from each zone.

15. The process y'of selectively absorbing olefin from hydrocarbon material containing olefins, which comprises introducing the hydrocarbon material to be treated. into an absorbing zone in direct contact with sulphuric acid, maintaining a temperature belovsr about -50 C. in said zone thereby to absorb the higher oleins in said material, passing the unabsorbed material from said zone into a second absorbing zone maintained at a higher temperature than said first mentioned zone but'beloW a temperature of about 20 C., and

in which the hydrocarbon material is brought into intimate contact with sulphuric acid,

maintaining the materials in each zone under pounds per square inch, and separately recovering the absorbed materials from cach Zone.

16. The process of selectively absorbing oleins from hydrocarbon material containing olefins, Which comprises introducing the hydrocarbon material to be treated into an absorbing zone in direct contact With sulphuric acid, maintaining a temperature below about -50 C. in said zone thereby to absorb the higher olefins in said material, passing the unabsorbed material from said zone into succeeding zones maintained at successively higher temperatures and in Which the hydrocarbon material is brought into intimate contact with sulphuric acid, maintaining the materials inv each zone under a pressure in excess of about fifty pounds per square inch, and separately removing materials absorbed in each zone.

17. The process of treating olefin-containing hydrocarbon material in the gaseous state, ,Which comprises bringing the material into intimate contact With cold sulphuric acid in a Contact Zone in Which a temperature bcloW about 50 C. is maintained, removing absorbed and liquefied materials from said zone, and separating the liquid unabsorbed material from the acid and absorbed material, passing gaseous unabsorbed material from said zone into a second absorbing zone in contact With sulphuric acidmaintained at a higher temperature, and separately recovering the absorbed material from said second zone.

ROBERT M. ISHAM. SIDNEY BORN. 

